Try to improve handling of failures during compilation

The change is mostly about trying to make sure the compiler "fails safe" when it encounters an internal assumption that isn't met.
Most internal errors will now throw exceptions (yes, exceptions are evil, but this will work for now), and these get caught in `spCompile` so that they don't propagate to the user (they just see a message that compilation aborted due to an internal error).

Subsequent changes are going to need to work on diagnosing as many of these situations as possible, so that users can at least know what construct in their code was unexpected or unhandled by the compiler.

1 files changed, 65 insertions, 58 deletions

diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp
index 2f009bb81..4754578b3 100644
--- a/source/slang/emit.cpp
+++ b/source/slang/emit.cpp
@@ -79,7 +79,6 @@ void requireGLSLVersion(
     ProfileVersion      version)
 {
     auto profile = entryPoint->profile;
-    auto currentVersion = profile.GetVersion();
     if (profile.getFamily() == ProfileFamily::GLSL)
     {
         // Check if this profile is newer
@@ -105,8 +104,8 @@ static String getStringOrIdentifierTokenValue(
     switch(token.Type)
     {
     default:
-        assert(!"unexpected");
-        return "";
+        SLANG_UNEXPECTED("needed an identifier or string literal");
+        break;
 
     case TokenType::Identifier:
         return token.Content;
@@ -600,7 +599,7 @@ struct EmitVisitor
                 {
                     Emit("\n");
                 }
-                assert(sourceLocation.Line == context->shared->loc.Line);
+                SLANG_RELEASE_ASSERT(sourceLocation.Line == context->shared->loc.Line);
             }
             else
             {
@@ -674,6 +673,10 @@ struct EmitVisitor
         emit(token.Content);
     }
 
+    DiagnosticSink* getSink()
+    {
+        return &context->shared->entryPoint->compileRequest->mSink;
+    }
 
     //
     // Types
@@ -691,7 +694,7 @@ struct EmitVisitor
         }
         else
         {
-            assert(!"unimplemented");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unknown type of integer constant value");
         }
     }
 
@@ -723,7 +726,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unknown declarator flavor");
             break;
         }
     }
@@ -742,8 +745,9 @@ struct EmitVisitor
             case BaseType::Int:		Emit("i");		break;
             case BaseType::UInt:	Emit("u");		break;
             case BaseType::Bool:	Emit("b");		break;
+            case BaseType::Double:	Emit("d");		break;
             default:
-                assert(!"unreachable");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled GLSL type prefix");
                 break;
             }
         }
@@ -757,7 +761,7 @@ struct EmitVisitor
         }
         else
         {
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled GLSL type prefix");
         }
     }
 
@@ -786,7 +790,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled resource access mode");
             break;
         }
 
@@ -798,7 +802,7 @@ struct EmitVisitor
         case TextureType::ShapeCube:	Emit("TextureCube");	break;
         case TextureType::ShapeBuffer:  Emit("Buffer");         break;
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled resource shape");
             break;
         }
 
@@ -830,7 +834,7 @@ struct EmitVisitor
         case TextureType::ShapeCube:	Emit("Cube");	break;
         case TextureType::ShapeBuffer:	Emit("Buffer");	break;
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled resource shape");
             break;
         }
 
@@ -876,7 +880,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled code generation target");
             break;
         }
     }
@@ -891,7 +895,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "this target should see combined texture-sampler types");
             break;
         }
     }
@@ -910,7 +914,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "this target should see GLSL image types");
             break;
         }
     }
@@ -959,8 +963,9 @@ struct EmitVisitor
         case BaseType::Float:	Emit("float");		break;
         case BaseType::UInt:	Emit("uint");		break;
         case BaseType::Bool:	Emit("bool");		break;
+        case BaseType::Double:	Emit("double");		break;
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled scalar type");
             break;
         }
 
@@ -992,7 +997,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled code generation target");
             break;
         }
 
@@ -1030,7 +1035,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled code generation target");
             break;
         }
 
@@ -1070,7 +1075,7 @@ struct EmitVisitor
             case SamplerStateType::Flavor::SamplerState:			Emit("SamplerState");			break;
             case SamplerStateType::Flavor::SamplerComparisonState:	Emit("SamplerComparisonState");	break;
             default:
-                assert(!"unreachable");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled sampler state flavor");
                 break;
             }
             break;
@@ -1081,7 +1086,7 @@ struct EmitVisitor
             case SamplerStateType::Flavor::SamplerState:			Emit("sampler");		break;
             case SamplerStateType::Flavor::SamplerComparisonState:	Emit("samplerShadow");	break;
             default:
-                assert(!"unreachable");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled sampler state flavor");
                 break;
             }
             break;
@@ -1170,7 +1175,10 @@ struct EmitVisitor
     {
         if (!typeExp.type || typeExp.type->As<ErrorType>())
         {
-            assert(typeExp.exp);
+            if (!typeExp.exp)
+            {
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unresolved type expression should have expression part");
+            }
 
             EDeclarator nameDeclarator;
             nameDeclarator.flavor = EDeclarator::Flavor::Name;
@@ -1344,7 +1352,7 @@ struct EmitVisitor
         }
         else
         {
-            assert(postOp);
+            SLANG_ASSERT(postOp);
             EmitExprWithPrecedence(arg, leftSide(outerPrec, prec));
         }
 
@@ -1394,7 +1402,7 @@ struct EmitVisitor
         switch(context->shared->target)
         {
         default:
-            assert(!"unexpected");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled code generation target");
             return false;
 
         case CodeGenTarget::GLSL: return targetName == "glsl";
@@ -1877,7 +1885,7 @@ struct EmitVisitor
                                 continue;
                             }
 
-                            assert(cursor != end);
+                            SLANG_RELEASE_ASSERT(cursor != end);
 
                             char d = *cursor++;
 
@@ -1888,7 +1896,7 @@ struct EmitVisitor
                                 {
                                     // Simple case: emit one of the direct arguments to the call
                                     UInt argIndex = d - '0';
-                                    assert((0 <= argIndex) && (argIndex < argCount));
+                                    SLANG_RELEASE_ASSERT((0 <= argIndex) && (argIndex < argCount));
                                     Emit("(");
                                     EmitExpr(callExpr->Arguments[argIndex]);
                                     Emit(")");
@@ -1906,7 +1914,7 @@ struct EmitVisitor
                                 }
                                 else
                                 {
-                                    assert(!"unexpected");
+                                    SLANG_UNEXPECTED("bad format in intrinsic definition");
                                 }
                                 break;
 
@@ -1914,7 +1922,7 @@ struct EmitVisitor
                                 // If we are calling a D3D texturing operation in the form t.Foo(s, ...),
                                 // then this form will pair up the t and s arguments as needed for a GLSL
                                 // texturing operation.
-                                assert(argCount > 0);
+                                SLANG_RELEASE_ASSERT(argCount > 0);
                                 if (auto memberExpr = callExpr->FunctionExpr.As<MemberExpressionSyntaxNode>())
                                 {
                                     auto base = memberExpr->BaseExpression;
@@ -1938,13 +1946,13 @@ struct EmitVisitor
                                     }
                                     else
                                     {
-                                        assert(!"unexpected");
+                                        SLANG_UNEXPECTED("bad format in intrinsic definition");
                                     }
 
                                 }
                                 else
                                 {
-                                    assert(!"unexpected");
+                                    SLANG_UNEXPECTED("bad format in intrinsic definition");
                                 }
                                 break;
 
@@ -1997,13 +2005,13 @@ struct EmitVisitor
                                         }
                                         else
                                         {
-                                            assert(!"unexpected");
+                                            SLANG_UNEXPECTED("bad format in intrinsic definition");
                                         }
 
                                     }
                                     else
                                     {
-                                        assert(!"unexpected");
+                                        SLANG_UNEXPECTED("bad format in intrinsic definition");
                                     }
                                 }
                                 break;
@@ -2013,7 +2021,7 @@ struct EmitVisitor
                                 // where `t` is a `Texture*<T>`, then this is the step where we try to
                                 // properly swizzle the output of the equivalent GLSL call into the right
                                 // shape.
-                                assert(argCount > 0);
+                                SLANG_RELEASE_ASSERT(argCount > 0);
                                 if (auto memberExpr = callExpr->FunctionExpr.As<MemberExpressionSyntaxNode>())
                                 {
                                     auto base = memberExpr->BaseExpression;
@@ -2043,19 +2051,19 @@ struct EmitVisitor
                                     }
                                     else
                                     {
-                                        assert(!"unexpected");
+                                        SLANG_UNEXPECTED("bad format in intrinsic definition");
                                     }
 
                                 }
                                 else
                                 {
-                                    assert(!"unexpected");
+                                    SLANG_UNEXPECTED("bad format in intrinsic definition");
                                 }
                                 break;
 
 
                             default:
-                                assert(!"unexpected");
+                                SLANG_UNEXPECTED("bad format in intrinsic definition");
                                 break;
                             }
                         }
@@ -2261,7 +2269,7 @@ struct EmitVisitor
             }
             else
             {
-                assert(!"unimplemented");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), litExpr, "unhandled type for integer literal");
             }
             Emit(litExpr->integerValue);
             Emit(suffix);
@@ -2283,7 +2291,7 @@ struct EmitVisitor
             }
             else
             {
-                assert(!"unimplemented");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), litExpr, "unhandled type for floating-point literal");
             }
             Emit(litExpr->floatingPointValue);
             Emit(suffix);
@@ -2296,7 +2304,7 @@ struct EmitVisitor
             emitStringLiteral(litExpr->stringValue);
             break;
         default:
-            assert(!"unreachable");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), litExpr, "unhandled kind of literal expression");
             break;
         }
         if(needClose) Emit(")");
@@ -2588,8 +2596,7 @@ struct EmitVisitor
             return;
         }
 
-        throw "unimplemented";
-
+        SLANG_UNEXPECTED("unhandled statement kind");
     }
 
     //
@@ -2716,7 +2723,7 @@ struct EmitVisitor
     {
         // Note(tfoley): any `typedef`s should already have been filtered
         // out if we are generating GLSL.
-        assert(context->shared->target != CodeGenTarget::GLSL);
+        SLANG_RELEASE_ASSERT(context->shared->target != CodeGenTarget::GLSL);
 
         Emit("typedef ");
         EmitType(decl->Type, decl->Name.Content);
@@ -2968,7 +2975,7 @@ struct EmitVisitor
         }
         else
         {
-            assert(!"unimplemented");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), semantic->Position, "unhandled kind of semantic");
         }
     }
 
@@ -3116,7 +3123,7 @@ struct EmitVisitor
             if (byteOffsetInRegister != 0)
             {
                 // The value had better occupy a whole number of components.
-                assert(byteOffsetInRegister % componentSize == 0);
+                SLANG_RELEASE_ASSERT(byteOffsetInRegister % componentSize == 0);
 
                 size_t startComponent = byteOffsetInRegister / componentSize;
 
@@ -3144,7 +3151,7 @@ struct EmitVisitor
                 Emit("s");
                 break;
             default:
-                assert(!"unexpected");
+                SLANG_DIAGNOSE_UNEXPECTED(getSink(), CodePosition(), "unhandled HLSL register type");
                 break;
             }
             Emit(info.index);
@@ -3192,7 +3199,7 @@ struct EmitVisitor
         if (!modifier) return nullptr;
 
         auto computedLayout = modifier->layout;
-        assert(computedLayout);
+        SLANG_RELEASE_ASSERT(computedLayout);
 
         auto varLayout = computedLayout.As<VarLayout>();
         return varLayout;
@@ -3208,18 +3215,18 @@ struct EmitVisitor
 
         // We expect/require the data type to be a user-defined `struct` type
         auto declRefType = dataType->As<DeclRefType>();
-        assert(declRefType);
+        SLANG_RELEASE_ASSERT(declRefType);
 
         // We expect to always have layout information
         layout = maybeFetchLayout(varDecl, layout);
-        assert(layout);
+        SLANG_RELEASE_ASSERT(layout);
 
         // We expect the layout to be for a structured type...
         RefPtr<ParameterBlockTypeLayout> bufferLayout = layout->typeLayout.As<ParameterBlockTypeLayout>();
-        assert(bufferLayout);
+        SLANG_RELEASE_ASSERT(bufferLayout);
 
         RefPtr<StructTypeLayout> structTypeLayout = bufferLayout->elementTypeLayout.As<StructTypeLayout>();
-        assert(structTypeLayout);
+        SLANG_RELEASE_ASSERT(structTypeLayout);
 
         if( auto constantBufferType = parameterBlockType->As<ConstantBufferType>() )
         {
@@ -3239,7 +3246,7 @@ struct EmitVisitor
         EmitSemantics(varDecl, kESemanticMask_None);
 
         auto info = layout->FindResourceInfo(LayoutResourceKind::ConstantBuffer);
-        assert(info);
+        SLANG_RELEASE_ASSERT(info);
         emitHLSLRegisterSemantic(*info);
 
         Emit("\n{\n");
@@ -3254,7 +3261,7 @@ struct EmitVisitor
                 EmitVarDeclCommon(field);
 
                 RefPtr<VarLayout> fieldLayout = structTypeLayout->fields[fieldIndex];
-                assert(fieldLayout->varDecl.GetName() == field.GetName());
+                SLANG_RELEASE_ASSERT(fieldLayout->varDecl.GetName() == field.GetName());
 
                 // Emit explicit layout annotations for every field
                 for( auto rr : fieldLayout->resourceInfos )
@@ -3273,7 +3280,7 @@ struct EmitVisitor
                         // If the member of the cbuffer uses a resource, it had better
                         // appear as part of the cubffer layout as well.
                         auto cbufferResource = layout->FindResourceInfo(kind);
-                        assert(cbufferResource);
+                        SLANG_RELEASE_ASSERT(cbufferResource);
 
                         offsetResource.index += cbufferResource->index;
                         offsetResource.space += cbufferResource->space;
@@ -3372,7 +3379,7 @@ struct EmitVisitor
 
         // We expect/require the data type to be a user-defined `struct` type
         auto declRefType = dataType->As<DeclRefType>();
-        assert(declRefType);
+        SLANG_RELEASE_ASSERT(declRefType);
 
         // We expect the layout, if present, to be for a structured type...
         RefPtr<StructTypeLayout> structTypeLayout;
@@ -3386,7 +3393,7 @@ struct EmitVisitor
             }
 
             structTypeLayout = typeLayout.As<StructTypeLayout>();
-            assert(structTypeLayout);
+            SLANG_RELEASE_ASSERT(structTypeLayout);
 
             emitGLSLLayoutQualifiers(layout);
         }
@@ -3413,7 +3420,7 @@ struct EmitVisitor
         }
         else
         {
-            assert(!"unexpected");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), varDecl, "unhandled GLSL shader parameter kind");
             Emit("uniform");
         }
 
@@ -3471,7 +3478,7 @@ struct EmitVisitor
             break;
 
         default:
-            assert(!"unexpected");
+            SLANG_DIAGNOSE_UNEXPECTED(getSink(), varDecl, "unhandled code generation target");
             break;
         }
     }
@@ -3696,7 +3703,7 @@ struct EmitVisitor
         }
         else
         {
-            throw "unimplemented";
+            SLANG_UNEXPECTED("unhandled declaration kind");
         }
     }
 };
@@ -3746,13 +3753,13 @@ String emitEntryPoint(
         auto elementTypeStructLayout = elementTypeLayout.As<StructTypeLayout>();
 
         // We expect all constant buffers to contain `struct` types for now
-        assert(elementTypeStructLayout);
+        SLANG_RELEASE_ASSERT(elementTypeStructLayout);
 
         globalStructLayout = elementTypeStructLayout.Ptr();
     }
     else
     {
-        assert(!"unexpected");
+        SLANG_UNEXPECTED("uhandled global-scope binding layout");
     }
     sharedContext.globalStructLayout = globalStructLayout;